South Africa's World Cup party might have started four days ago in a riot of colour and a frenzy of noise, but the world has been forced to wait until now for the guests of honour to arrive.

Yet while Brazil, clad in those iconic yellow shirts, will look every inch the great entertainers when they walk out under the Ellis Park floodlights to face North Korea, something has changed. This is Brazil, but not as we know them.

Gone is the over-elaboration which afflicted the side dubbed the Magic Square in Germany four years ago. Gone are many of the star names, most notably Ronaldinho, those players feted in Brazil for their wizardry, their slight of foot. Gone is the dogma that the country must produce sides to honour the ghosts of 1970 and 1982, however pale the imitation.

Under the disciplinarian reign of Dunga, the dour, serious coach who won the tournament as dour, serious captain in 1994, Brazil have cast out their artists – or at least the most mercurial of them – in favour of assassins.

Forget the parlour tricks designed for the highlights reel. Dunga does not want conjurors. He wants cobras.

The transition to the manager's style, one of patience and control followed by quick, lethal strikes, has not been a simple one. He has faced ferocious criticism since he replaced his mentor, Carlos Alberto Parreira, in the aftermath of acrimonious quarter-final elimination in 2006.

Even their serene progress to this tournament, even victory in the Confederations Cup last year and in the Copa America in 2007 could not staunch the flow of barbs from figures such as Tostao, the hero of 1970 turned influential television commentator.

Brazil, so the theory goes, are not employing their players correctly, not maximising the potential of the country's rich seam of talent. They are viewed as Dunga's playing style writ large, a suspicion fuelled by his tense relationship with Kaka, the one player considered to be maintaining Brazil's tradition of the inspirational.

Dunga, predictably, remains devoted to his philosophy. "The criticism is not unjust," he says, "but it is just a point of view. The criticism is always that we are defensive, but we have scored over 100 goals, conceding only 30.

"We are a balanced team. Sometimes the experts are wrong. Germany were criticised in qualifying, but they scored four goals [against Australia]. It does not matter what people say. It is what happens on the field." Perhaps that is why Dunga retains the unquestioning loyalty of his players.

Gilberto Silva, the former Arsenal midfielder and a player cast in his manager's mould, makes an admittedly likely loyalist, but he remembers with bitterness the 2006 campaign, when Brazil's much-vaunted side containing Kaka, Robinho and Ronaldinho were undone by the internecine squabbling linked to a collection of such high-profile stars.

"The way he works is very simple, but very clear to the players," Silva said. "We are difficult for opponents. We can change from one style to another, from our proper way of playing that everyone knows to a defensive style. We can control the game and then, in the end, play very quickly. We have created this identity and we can change according to the situation we face.

"I have seen a lot of articles trying to crucify him and his style of work, the way he does his job, everything, but I am sure he is doing what is best for the national side.

"Last tournament we had a bad experience in some things and he has changed it. All of the players are united behind him."

Brazil, though, know that such unity can be fleeting. Dunga is never likely to be as popular in his homeland as Tele Santana, the coach of the 1982 vintage, the greatest team never to win the World Cup, but the condemnation will be total if his Brazil are unattractive, at least by their own high standards, and unsuccessful.

Yet there, too, he has the backing of his players. Luis Fabiano, the striker whose ceaseless motion and ruthless finishing glues Dunga's system together, is circumspect in explaining their confidence. "It works. Playing like this, we have won a lot of games."

To the rest of the world, those yellow shirts signify that the entertainment has arrived. The new Brazil, though, are not here for fun. They are here to win.